1. Field of the Invention
This invention is in the field of semiconductor wafer processing and, more particularly, relates to providing an electrically conductive path from a source of radio frequency power to an assembly wherein a plasma field is maintained.
2. Description of the Prior Art
A plasma enhanced vapor reactor is typically used in a deposition process for coating a semiconductor wafer. Usually, a plurality of semiconductor wafers are serially arranged within what is known as a semiconductor wafer boat assembly. During the process, the boat assembly is maintained in a tube where the temperature is elevated and gas reactants are passed.
An essential feature of the process is the establishment of a plasma field near the wafers. The field is established by providing an radio frequency voltge to electrodes of the boat. The leads that connect to the electrode, as well as supporting structures, are usually sheathed in a ceramic to prevent an undesired plasma field along the leads and the supporting structures.
Typically, the boat includes a pair of contacts that are connected via the leads of a source of radio frequency power. The source is external to the tube. Usually, the leads have contact surfaces that are maintained in an abutting relationship with the boat contacts. Attempts have been made to maintain the abutting relationship through the use of springs. However, because of the elevated temperature, the springs anneal and become useless.
Heretofore, there has not been an economical and reliable apparatus that provides a connection to the boat contacts.